The present invention relates to a plastic container for the controlled delivery powders and of liquids as drops, and provided with a piercing closure capsule which is actuatable at the time of use. Thus, a vial made from a flexible plastic material is equipped with a capsule provided with a piercing element, which allows the opening to be accomplished. The device is particularly suitable for the dispensing of liquids, for example, the dropwise administration, of pharmaceuticals or powders.
The state of the art comprises vials of plastic material or glass, provided with a stem dropper, which must be inserted or screwed down to allow the liquid contained in the vials to be delivered. Furthermore, plastic vials are known, the outlet mouth of which can be activated by the tearing of a shutter provided with a grip tab actuatable by torsion. However, the stem dropper is not hygienic, is expensive and involves auxiliary operations. On the other hand, the tearable dropper does not result in a hygienic operation as related to the re-use of the shutter, and, furthermore, it does not provide a calibrated flow of drops, particularly because of the fringes generated by the tearing of the outlet orifice.
Thus the state of the art can be improved as it relates to the possibility of overcoming the above-indicated drawbacks.
From the above, there has been identified a need for solving the technical problem of providing a device for a plastic vial which allows the outlet mouth of the vial to be closed and controlled for achieving a hygienic seal and permits a delivery of the liquid contents as uniform drops and that in a manner which is simple, convenient and inexpensive.
The present invention solves the above technical problems by adopting a container made from a flexible plastic material, either as an isolated piece, or as a piece in series with other pieces, provided with a threaded neck having an axial, cylindrical tubular extension with a transverse membrane-diaphragm, and upstream of said extension an outlet mouth having a divergent cone-frustum shape. The outlet bore of said extension is calibrated, and has a diameter larger than the minimum diameter of said outlet mouth. On the outer surface of the said extension a circumferential groove is provided. The capsule for sealing, piercing, and subsequently closing the container, is provided with an outer operation tab, and has on its inner wall a first threaded length for permitting it to be coupled with the thread provided the on container neck at the end of the threaded length, towards the inside of the capsule a restraint ring protrudes, which is destined to become engaged in a springwise fashion inside said groove in order to guarantee sealing. From the bottom of the same capsule a piercing element protrudes in the axial direction, which is suitable for piercing said membrane and causing the edges thereof to adhere to the inner surface of the bore of said cylindrical neck extension, so is to equalize the inner diameter of the bore to the minimum diameter of the cone-frustum shaped outlet mouth. Due to the effect of screwing down of the capsule onto the neck, the restraint ring deforms and leaves the related groove, to follow the forward motion of the capsule.
The advantages of the present invention include a warranty seal, obtained by means of the transversal diaphragm and the coupling of the restraint ring of the capsule with the groove provided in the neck extension; the initial delivery of the liquid by piercing the diaphragm by the piercing element provided inside the capsule; metering the drops due to the effect of providing the flare downstream of the diaphragm with the adhesion of the edges of the diaphragm to the inner surface of the outlet bore provided in the extension of the container neck; possible re-use of the container; in case of a multi-dose container, with the hygienic re-applying of the capsule to the neck of the same container; operation simpleness; and low cost.